protected override Expression VisitDeclaration(DbDeclarationCommand decl) { if (decl.Source != null) { var projection = new DbProjectionExpression ( decl.Source, Expression.NewArrayInit(typeof(object), decl.Variables.Select(v => v.Expression.Type.GetTypeInfo().IsValueType ? Expression.Convert(v.Expression, typeof(object)) : v.Expression).ToArray()), DbAggregator.GetAggregator(typeof(object[]), typeof(IEnumerable <object[]>)) ); var vars = Expression.Parameter(typeof(object[]), "vars"); this.variables.Add(vars); this.initializers.Add(Expression.Constant(null, typeof(object[]))); for (int i = 0, n = decl.Variables.Count; i < n; i++) { var v = decl.Variables[i]; var nv = new DbNamedValueExpression ( v.Name, v.QueryType, Expression.Convert(Expression.ArrayIndex(vars, Expression.Constant(i)), v.Expression.Type) ); this.variableMap.Add(v.Name, nv); } return(MakeAssign(vars, this.Visit(projection))); } throw new InvalidOperationException("Declaration query not allowed for this langauge"); }
public override Expression GetMemberExpression(Expression root, MappingEntity entity, MemberInfo member) { if (this.mapping.IsAssociationRelationship(entity, member)) { var relatedEntity = this.mapping.GetRelatedEntity(entity, member); var projection = this.GetQueryExpression(relatedEntity); var declaredTypeMembers = this.mapping.GetAssociationKeyMembers(entity, member).ToList(); var associatedMembers = this.mapping.GetAssociationRelatedKeyMembers(entity, member).ToList(); var where = null as Expression; for (int i = 0, n = associatedMembers.Count; i < n; i++) { var equal = this.GetMemberExpression ( projection.Projector, relatedEntity, associatedMembers[i]).Equal(this.GetMemberExpression(root, entity, declaredTypeMembers[i]) ); where = (where != null) ? where.And(equal) : equal; } var newAlias = new TableAlias(); var pc = DbColumnProjector.ProjectColumns ( this.translator.Linguist.Language, projection.Projector, null, newAlias, projection.Select.Alias ); var aggregator = DbAggregator.GetAggregator(TypeHelper.GetMemberType(member), typeof(IEnumerable <>).MakeGenericType(pc.Projector.Type)); var result = new DbProjectionExpression ( new DbSelectExpression(newAlias, pc.Columns, projection.Select, where), pc.Projector, aggregator ); return(this.translator.Police.ApplyPolicy(result, member)); } if (root is DbAliasedExpression aliasedRoot && this.mapping.IsColumn(entity, member)) { return(new DbColumnExpression ( TypeHelper.GetMemberType(member), this.GetColumnType(entity, member), aliasedRoot.Alias, this.mapping.GetColumnName(entity, member) )); } return(DbQueryBinder.BindMember(root, member)); }
protected virtual Expression GetUpdateResult(MappingEntity entity, Expression instance, LambdaExpression selector) { var tq = this.GetQueryExpression(entity); var where = this.GetIdentityCheck(tq.Select, entity, instance); var selection = DbExpressionReplacer.Replace(selector.Body, selector.Parameters[0], tq.Projector); var newAlias = new TableAlias(); var pc = DbColumnProjector.ProjectColumns(this.translator.Linguist.Language, selection, null, newAlias, tq.Select.Alias); return(new DbProjectionExpression ( new DbSelectExpression(newAlias, pc.Columns, tq.Select, where), pc.Projector, DbAggregator.GetAggregator(selector.Body.Type, typeof(IEnumerable <>).MakeGenericType(selector.Body.Type)) )); }
protected override Expression VisitExists(DbExistsExpression exists) { var colType = this.linguist.Language.TypeSystem.GetColumnType(typeof(int)); var newSelect = exists.Select.SetColumns(new[] { new DbColumnDeclaration("value", new DbAggregateExpression(typeof(int), "Count", null, false), colType) }); var projection = new DbProjectionExpression ( newSelect, new DbColumnExpression(typeof(int), colType, newSelect.Alias, "value"), DbAggregator.GetAggregator(typeof(int), typeof(IEnumerable <int>)) ); return(this.Visit(projection.GreaterThan(Expression.Constant(0)))); }
protected virtual Expression GetInsertResult(MappingEntity entity, Expression instance, LambdaExpression selector, Dictionary <MemberInfo, Expression> map) { var tableAlias = new TableAlias(); var tex = new DbTableExpression(tableAlias, entity, this.mapping.GetTableName(entity)); var aggregator = DbAggregator.GetAggregator(selector.Body.Type, typeof(IEnumerable <>).MakeGenericType(selector.Body.Type)); var where = null as Expression; var genIdCommand = null as DbDeclarationCommand; var generatedIds = this.mapping.GetMappedMembers(entity).Where(m => this.mapping.IsPrimaryKey(entity, m) && this.mapping.IsGenerated(entity, m)).ToList(); if (generatedIds.Count > 0) { if (map == null || !generatedIds.Any(m => map.ContainsKey(m))) { var localMap = new Dictionary <MemberInfo, Expression>(); genIdCommand = this.GetGeneratedIdCommand(entity, generatedIds.ToList(), localMap); map = localMap; } if (selector.Body is MemberExpression mex && this.mapping.IsPrimaryKey(entity, mex.Member) && this.mapping.IsGenerated(entity, mex.Member)) { if (genIdCommand != null) { return(new DbProjectionExpression ( genIdCommand.Source, new DbColumnExpression(mex.Type, genIdCommand.Variables[0].QueryType, genIdCommand.Source.Alias, genIdCommand.Source.Columns[0].Name), aggregator )); } else { var alias = new TableAlias(); var colType = this.GetColumnType(entity, mex.Member); return(new DbProjectionExpression ( new DbSelectExpression(alias, new[] { new DbColumnDeclaration(string.Empty, map[mex.Member], colType) }, null, null), new DbColumnExpression(TypeHelper.GetMemberType(mex.Member), colType, alias, string.Empty), aggregator )); } } where = generatedIds.Select((m, i) => this.GetMemberExpression(tex, entity, m).Equal(map[m])).Aggregate((x, y) => x.And(y)); } else { where = this.GetIdentityCheck(tex, entity, instance); } var typeProjector = this.GetEntityExpression(tex, entity); var selection = DbExpressionReplacer.Replace(selector.Body, selector.Parameters[0], typeProjector); var newAlias = new TableAlias(); var pc = DbColumnProjector.ProjectColumns(this.translator.Linguist.Language, selection, null, newAlias, tableAlias); var pe = new DbProjectionExpression ( new DbSelectExpression(newAlias, pc.Columns, tex, where), pc.Projector, aggregator ); if (genIdCommand != null) { return(new DbBlockCommand(genIdCommand, pe)); } return(pe); }